Formation of New Fermi Surfaces in 3D Crystals at Ultra High Magnetic Field with Different Orientations

TL;DR

This paper investigates how ultra-high magnetic fields with different orientations can induce the formation of new Fermi surfaces in three-dimensional crystal lattices, using a tight-binding model and Harper-like equations.

Contribution

It derives a Harper-like equation for 3D electrons in magnetic fields and analyzes Fermi surface formation at specific flux ratios and orientations.

Findings

New Fermi surfaces form at specific magnetic flux ratios.

Magnetic field orientation affects Fermi surface topology.

Quantization rules vary slightly with flux deviations.

Abstract

In the tight-binding approximation the Harper like equation describing an electron in 3D crystal subject to a uniform magnetic field is obtained. It is supposed that the vector H can be oriented along several directions in the lattice. The Fermi surfaces relevant to a magnetic flux p/q=1/2 in a simple cubic lattice are built. The quantization rules in magnetic fields slightly distinguished from p/q=1/2 are investigated.